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Successes We May Not Have Had: A Retrospective Analysis of Selected Weed Biological Control Agents in the United States

Published online by Cambridge University Press:  20 January 2017

Hariet L. Hinz*
Affiliation:
CABI Switzerland, Rue des Grillons 1, 2800 Delémont, Switzerland
Mark Schwarzländer
Affiliation:
Department of Plant Soil and Entomological Sciences, University of Idaho, Moscow ID, 83844-2339
André Gassmann
Affiliation:
CABI Switzerland, Rue des Grillons 1, 2800 Delémont, Switzerland
Robert S. Bourchier
Affiliation:
Agriculture and Agri-Food Canada, Lethbridge, Canada
*
Corresponding author's E-mail: [email protected]
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Abstract

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In this paper, we describe five successful classical biological weed control agents released in the United States. For each of the five arthropod species, we compared data from prerelease studies that experimentally predicted the agent's host range with data collected postrelease. In general, experimental host range data accurately predicted or overestimated risks to nontarget plants. We compare the five cases with insects recently denied for introduction in the United States and conclude that none of the discussed agents would likely be approved if they were petitioned today. Three agents would be rejected because they potentially could attack economic plants, and two because of potential attack on threatened or endangered plants. All five biocontrol agents have contributed significantly to the successful management of major weeds with no or minimal environmental risk. We believe that the United States may miss opportunities for sustainable and environmentally benign management of weeds using biological control if the regulatory framework only considers the risks of agents as potential plant pests and treats any host-range data regarding economic or threatened and endangered species as a binary decision (i.e., mandates rejection if there is any chance of feeding or development). As a way forward we propose the following: (1) the addition of risk and benefit analyses at the habitat level with a clear ranking of decision-making criteria as part of the U.S. Department of Agriculture Animal and Plant Health Inspection Service Technical Advisory Group's evaluation process of biocontrol agents; (2) recognition of the primacy of realized host range data for potential agents that considers the insect's host selection behavior instead of emphasizing fundamental host range data during release evaluations, and (3) development of formalized postrelease monitoring of target and nontarget species as part of the release permit. These recommendations may initially be advanced through reassessment of current policies but may in the longer term require the implementation of dedicated biocontrol legislation.

Type
Research Article
Creative Commons
Creative Common License - CCCreative Common License - BY
This is an Open Access article, distributed under the terms of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited.
Copyright
Copyright © Weed Science Society of America

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